Devices have been used in the past for the purpose of keeping the cable tautened in the applications noted above, and these have involved use of roller or sheave means for pressural engagement with the cable to accomplish tautening of the cable outside of or beyond the drum. In all cases of which I am aware, however, there exists an inherent disadvantageous feature in that the cable is constrained to slip relative to the roller or sheave. This condition results in wear on the cable requiring its premature replacement. A primary purpose of the present invention is the reorganization of such systems to remove slip and wear from the cable and transfer it to one or more slip clutches, which can be replaced much more easily and less expensively than can be cable itself.
The invention itself can best be described through reference to the accompanying drawings showing selected present illustrative embodiments thereof.